title: A gauge invariant multiscale approach to magnetic spectroscopies in condensed phase: general three-layer model, computational implementation and pilot applications.
abstract: Analytical equations to calculate second order electric and magnetic properties of a molecular system embedded into a polarizable environment are presented. The treatment is limited to molecules described at the self consistent field level of theory, including Hartree-Fock theory as well as Kohn-Sham density functional theory and is extended to the Gauge-Including Atomic Orbital method. The polarizable embedding is described by means of our already implemented polarizable quantum mechanical/molecular mechanical (MM) methodology, where the polarization in the MM layer is handled by means of the fluctuating charge (FQ) model. A further layer of description, i.e, the polarizable continuum model, can also be included. The FQ(/polarizable continuum model) contributions to the properties are derived, with reference to the calculation of the magnetic susceptibility, the nuclear magnetic resonance shielding tensor, electron spin resonance g-tensors, and hyperfine couplings.
authors.affiliation: Scuola Normale Superiore, Piazza dei Cavalieri, 7 I-56126 Pisa, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Lipparini
authors.forename: Chiara
authors.initials: C
authors.lastname: Cappelli
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Barone